Creates an instance of a routing circuit adjacency.  An
    adjacency describes a neighboring node that is accessible
    through a particular circuit.

    This create command is allowed only if the circuit is a
    csma-cd circuit and the type is L1router or L2router.

    create  [node node-id] routing circuit circuit-name -
                   adjacency adjacency-name, -
                   endnode ids {id[,id...]}, -
                   LAN address LAN-address [,data format string]

    The required Endnode IDs argument is a set of source system
    IDs.  The required LAN Address argument is the Data Link
    address from which the adjacency receives end system hellos.
    The optional Data Format argument is the format of the reachable
    address.